With the development of communications technology, multipoint conference systems are now being broadly used. Through the multipoint conference system, a conference with several sites at the same time can be held. Referring to FIG. 1, a multipoint conference system usually includes a multipoint control unit (MCU), an MCU management station, and several terminals. The terminals include common conference participation terminals and chairman terminals designated from the conference participation terminals. The multipoint conference system can support the access of a circuit switched network and a packet switched network. The terminals that access to the conference may be H.323 terminals, E1 terminals, Integrated Services Digital Network (ISDN) terminals, Public Switched Telephone Network (PSTN) terminals, and so on.
In a multipoint conference, when calling a called terminal fails, a manager or a call initiator of the multipoint conference is usually indicated with a reason why the call failed. A method for indicating call failure in prior art includes the following blocks:
(1) An MCU sends a call request including called terminal information to a switch of a called terminal.
(2) The switch calls the called terminal according to the call request.
(3) If the call fails, the switch determines the reason of the call failure, and returns identification information of the call failure reason to the MCU.
(4) The MCU sends the identification information of the call failure reason to an MCU management station or a chairman terminal. According to a mapping relationship between the preset identification information and voice information of the call failure reason, the MCU management station or the chairman terminal obtains the voice information of the call failure reason corresponding to the identification information, and then plays the voice information.
In the implementation of the present invention, the inventors found that the prior art at least has the following problems: To indicating the manager or the call initiator of the multipoint conference with the call failure reason through a voice, the call failure reason should be recorded and stored in advance on the MCU management station or on the terminals serving as the chairman terminals, which is cumbersome and occupies too many storage resources.